Sealing system

ABSTRACT

A sealing system has a gasket ( 25 ) which in the undeformed state can be placed against a component ( 1 ) to be sealed and in the deformed state engages the component ( 1 ) such that the gasket ( 25 ) is captively held on the component ( 1 ).

The invention relates to a sealing system with a gasket that can beplaced against an assigned component in order to form a seal on it.

In industrial production processes, with respect to achieving ahigh-speed and efficient operating sequence, it is prior art to useprefabricated components for assembly or installation activities. Thus,for example, in the production of systems that enclose or relay flowablemedia and in which seals on components are necessary, components onwhich the pertinent gasket has already been placed are often madeavailable for final installation processes. A component which has beenpremounted in this way promotes simple, high-speed and efficientexecution of a subsequent, final installation process, but complicationof the working step of transfer between the premounted component andfinal assembly station must be tolerated. In this connection thepremounted component must be handled such that the danger of the gasketfalling off the component or being lost in the transfer phase isavoided.

Proceeding from this prior art, the object of the invention is to makeavailable a sealing system in which a gasket that has been placed on thepertinent component is captively locked on it.

This object is achieved as claimed in the invention by a sealing systemthat has the features of claim 1 in its entirety.

Accordingly the invention calls for the gasket to be made such thatafter it is placed against the pertinent component it captively engagesit by deformation. By means of a simple premounting process in whichaction is applied to the gasket by deformation, the result is that thegasket is held “captively” on the component until complete installationso that the component can be handled after premounting without the needfor measures to keep the gasket on the component in the transitionphase.

In advantageous exemplary embodiments in which the gasket is designed toform an axial seal and surrounds the longitudinal axis along one contactsurface with the component, on the gasket preferably at least onematerial part is made such that in the undeformed state it projects inthe axial direction and defines a first radial distance of the edge areaof the gasket from the longitudinal axis, and that in the deformed stateit is flattened and brought near the contact surface and defines asecond radial distance from the longitudinal axis.

In an especially simple and advantageous manner in these exemplaryembodiments deformation takes place by simply pressing the gasket flat,for example by means of a plunger which presses the gasket flat on thecontact surface.

As the material part projecting in the axial direction in the undeformedstate, there can be at least one bead which extends along the edge ofthe gasket and which can be pressed flat as the gasket passes into thedeformed state in order to change the radial distance of the outsideperiphery or of the inner edge of the gasket from the longitudinal axis.

Alternatively, the material part projecting out of the main plane of thegasket in the undeformed state can be at least one retaining projectionwhich is located on the edge of the gasket and which is raised obliquelyin the undeformed state out of the main plane of the seal, preferablythere being several obliquely raised retaining projections which aredistributed along the outside peripheral edge of the gasket.

Alternatively these retaining projections can be arranged distributedaround the inside edge of the gasket.

As the retaining means on the component which the pertinent gasketengages by deformation, the component can have a flange which forms thecontact surface for the gasket, on the peripheral edge of the flangethere being an enclosure which protrudes axially from the contactsurface and that has an undercut which is opened radially to the insideand which the gasket engages with the material part which increases itsradial distance from the longitudinal axis during deformation.

In gaskets in which the radial distance from the longitudinal axis isreduced upon deformation on the inner edge of the gasket, the contactsurface with the component can form an axially protruding innerenclosure for the gasket which has an undercut that is opened radiallyto the inside and which the gasket engages with the material part whichreduces its radial distance from the longitudinal axis duringdeformation.

The invention is explained below in detail with reference to theexemplary embodiments illustrated in the drawings, in which:

FIG. 1 shows a cutaway axial section of a component which is to besealed with a flange that has a contact surface for a gasket, the gasketbeing shown in the undeformed state before it is placed against thecontact surface and a deformation device in the form of a movableplunger being shown before moving up to the gasket;

FIG. 2 shows a section corresponding to FIG. 1 with a deformed gasketlocated on the contact surface;

FIG. 3 shows a perspective view of a gasket for one embodiment of thesealing system as claimed in the invention which has been modifiedcompared to FIGS. 1 and 2;

FIG. 4 shows a perspective oblique view of an embodiment of the sealingsystem using the gasket from FIG. 3, the gasket being shown captivelylocked on the component in the deformed state;

FIG. 5 shows a perspective oblique view of a gasket for a furthermodified exemplary embodiment of the sealing system;

FIG. 6 shows an overhead view of the gasket from FIG. 5, however thedeformed state of the sealing ring being shown;

FIG. 7 shows a cutaway axial section of the embodiment of the sealingsystem as claimed in the invention which uses the gasket from FIGS. 5and 6, the gasket in the deformed state being shown captively locked,and

FIG. 8 shows the axial section of the gasket from FIGS. 5 and 6 in theundeformed state, before being placed against the component and beforedeformation by means of the hollow plunger shown in the cutaway axialsection.

FIG. 1 shows the end section of a pipeline 1 with a flange 3, on whichthe line 1 is to be connected to a continuing system component (notshown) with formation of a seal. The pipeline 1 can be for example theexhaust gas line in conjunction with the turbocharger system of aninternal combustion engine. Such a component is sealed withconsideration of the high temperature of the flowing medium (exhaustgas) preferably by means of a gasket of metallic material. FIG. 1 showsa gasket 5 of ordinary metallic sealing material which is suitable forthese sealing purposes. The gasket 5 is shown before it is placedagainst the pertinent seal contact surface 7 which, like the gasket,surrounds a central longitudinal axis 9.

FIG. 1 shows the gasket 5 in the undeformed state, it being apparentthat the gasket 5 along its outer peripheral edge has a material part inthe form of a larger bead 11 which surrounds a smaller bead 13 whichlies radially farther to the inside.

FIG. 2 shows the gasket 5 in the “installed” state, the gasket 5 beingdeformed by the bead 11 being pressed flat. Deformation takes place bymeans of a plunger 15 which is shown in FIG. 1 and which is moved in thedirection of the arrow 17 so that with its pressing surface 19 it pushesthe gasket 5 against the contact surface 7 and in doing so presses thebead 11 flat. While in the undeformed state the outer peripheral edge ofthe gasket 5 has a radial distance from the longitudinal axis 9 whichenables it to adjoin the contact surface 7, with an access opening onthe flange 3 bordered by an outer enclosure 21 which projects axiallyout of the contact surface 7, the outside diameter of the gasket 5 hasbeen enlarged by pressing the bead 11 flat to such an extent (see FIG.2) that the gasket 5 is prevented from being lifted out of the flange 3by the enclosure 21. This enclosure 21 has an undercut 23 which adjoinsthe contact surface 7 which the peripheral edge of the deformed gasket 5engages so that it is locked captively on the flange 3 of the line 1 bymeans of the enclosure 21 which forms a retaining means.

FIGS. 3 and 4 show one modified example with a metallic gasket 25 inwhich, instead of a bead provided as a deformable material part, fourretaining projections 27 are molded on, which have a rounded shape,which are raised axially obliquely out of the main seal plane, and whichare distributed on the outside peripheral edge of the gasket 25. FIG. 3shows the gasket 25 in the undeformed state before it is brought (in thedirection of the arrow 29) up to the flange 3 of the pipeline 1 to besealed. Instead of the external enclosure 21 of the flange 3 shown forthe example from FIG. 1 and FIG. 2, with the undercut 23 made in theenclosure 21, on the flange 3 of the example from FIG. 4 the peripheraledge of the flange 33 is provided to the inside with a slight border 31which forms an undercut by way of the seal contact surface 7. While thegasket 25 in the undeformed state can be placed against the contactsurface 7 through the inside edge of the border 31, the retainingprojections 27 engage the undercut under the border 31 as soon as thegasket 25 is deformed by pressing flat, by which the retainingprojections 27 widen to the outside when pressure is applied to thecontact surface 7 (FIG. 4).

FIGS. 5 and 6 show a gasket 35 made likewise from metallic material fora modified embodiment, FIG. 5 showing the gasket 35 in the undeformedstate and FIG. 6 showing the deformed state of the gasket 35. Incontrast to the example from FIGS. 3 and 4, there are retainingprojections 37 which are obliquely raised out from the gasket plane, ina distributed arrangement on the inside edge of the gasket 35. FIGS. 7and 8 illustrate the application principle of the gasket 35. As FIG. 7shows, the seal contact surface 7 on the flange 3 of the component to besealed on the inner edge of the contact surface 7 has an enclosure 39 inwhich an undercut 41 which adjoins the inside edge of the contactsurface 7 is formed. FIG. 8 shows the undeformed gasket 35 before movingto the contact surface 7 (FIG. 7) in the direction of the arrow 43 andbefore moving the deforming pipe plunger 45 in the direction of thearrow 47. In the undeformed state the end edges 49 of the retainingprojections 37 have a radial distance from the longitudinal axis suchthat the gasket 35 can be pushed over the enclosure 39. But if theretaining projections 37 are placed flat against the contact surface 7by means of the plunger 45, the end edges 49 of the retainingprojections 37 extend into the undercut 41 of the edge 39 so that thegasket 35 is in turn captively locked. As is most apparent from FIG. 6,the end edges 49 of the retaining projections 37 are not rounded, as isthe case for the end edges 49 of the retaining projections 27 of theexample from FIGS. 3 and 4, but run along the arc segment relative tothe longitudinal axis.

1. A sealing system with a gasket (5; 25; 35) which in the undeformedstate can be placed against a component (1) to be sealed and in thedeformed state engages the component (1) such that the gasket (5; 25;35) is captively held on the component (1).
 2. The sealing system asclaimed in claim 1, wherein the gasket (5; 25; 35) is designed to forman axial seal and surrounds the longitudinal axis (9) along one contactsurface (7) on the component (1) and wherein on the gasket (5; 25; 35)at least one material part (11; 27; 37) is made such that in theundeformed state it projects in the axial direction and defines a firstradial distance of the edge area of the gasket (5; 25; 35) from thelongitudinal axis (9) and wherein in the deformed state it is flattenedand brought near the contact surface (7) and defines a second radialdistance from the longitudinal axis (9).
 3. The sealing system asclaimed in claim 2, wherein as the material part projecting in the axialdirection in the undeformed state there is at least one bead (11) whichextends along the edge of the gasket (5) and which can be pressed flatas the gasket (5) passes into the deformed state in order to change theradial distance of the outside periphery or of the inner edge of thegasket (5) from the longitudinal axis (9).
 4. The sealing system asclaimed in claim 2, wherein the material part projecting out of the mainplane of the gasket (25; 35) in the undeformed state is at least oneretaining projection (27, 37) which is located on the edge of the gasket(25; 35) and which is raised obliquely in the undeformed state out ofthe main plane of the seal.
 5. The sealing system as claimed in claim 4,wherein there are several obliquely raised retaining projections (27)which are distributed along the outside peripheral edge of the gasket(25).
 6. The sealing system as claimed in claim 4, wherein there areseveral obliquely raised retaining projections (37) which aredistributed around the inside edge of the gasket (35).
 7. The sealingsystem as claimed in claims 1, wherein the component (1) has a flange(3) which forms the contact surface (7) for the gasket (5; 25), on theperipheral edge of the flange there being an enclosure (21; 31) whichprotrudes axially from the contact surface (7) and which has an undercut(23) that is opened radially to the inside and that the gasket (5; 25)engages with the material part which increases its radial distance fromthe longitudinal axis (9) during deformation.
 8. The sealing system asclaimed in claim 6, wherein the component (1) on the end of the contactsurface (7) intended for the gasket (35), which end lies radially to theinside, forms an axially projecting inner enclosure (39) for the gasket(35) which has an undercut (41) which is opened radially to the outsideand which the gasket (35) engages with the material part (37) whichreduces its radial distance from the longitudinal axis (9) duringdeformation.